Process of making oils nonsludging



Patented Nov. 6, 1923.

UNETE$ STATES HERBERT RAYMOND MOODY, OF NEW YORK, N. Y.

PROCESS OF MAKING OILS NONSLUDGING.

Ho Drawing.

To all whom it may concern:

Be it known that I, HERBERT R. MOODY, a citizen of the United States,residing at No. 330 Convent Avenue, New York city, in the county of NewYork, State of New York, have invented certain new and usefulImprovements in Processes of Making Oils Nonsludging; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and usethe same.

This invention relates to the treatment of unsaturated organic liquids,and particularly to the treatment of petroleum fractions, havingdefinite electrical mechanical and chemical properties, in order to makethem non sludging when subjected (with or without contact with copper orother metal) to an oxidizing heat treatment.

In oils such as are used, for example, in electrical transformers, orsuch as are used as insulating or cooling liquids, or for lubrication invarious forms of electrical or mechanical apparatus, it is importantthat the oils should not sludge. The common methods of purifying suchpetroleum fractions do not free them from sludgeforming constituents,and, upon use under conditions where they are subjected to heat and tooxidation, such oils frequently have sludge of an objectionable natureformed therein.

It is an object of the present invention to remove from such oils theirsludge-forming constituents and properties, and to impart to the oilsimproved properties and qualities which adapt them particularly for usefor purposes such as those noted above.

According to the present invention, the oil, such as petroleum fractionof a consistency adapted for the intended purpose, after properfractionation, filtration, or other clarification treatment, is digestedwith caustic alkali and with an appropriate metal in a suitable state ofsubdivision or comminution. It has been found that in practice the bestmetals are those which are'the most electro-negative to the alkalimetals and form salts therewithf Among these metals may be mentionedzinc, which forms Zincatcs, aluminum which forms aluminates, iron whichforms ferrates, tin. which forms stannates. etc. Scrap tinned iron plateis also available for use. The oil, caustic alkali, and metal, areheated to Application filed February 6, 1918.

Serial No. 215,715.

the appropriate temperature for a sufiicient time to enable the desiredaction to take place, the action being promoted, if desired, bycontinuous agitation, or by otherwise bringing the oil into intimatecontact with the metal and alkali. After the treatment, the salts formedcan be separated from the oil in any suitable manner, as by washing, andshould in practice be separated where their presence would bedetrimental in the treated oil, for example, where their presence woulddecrease the electrical resistance of oil intended for insulatingpurposes.

The action can be further promoted by the presence of metals which donot combine with the alkali metals in the manner above indicated butwhich act catalytically, and therebyfacilitate or promote the desiredreaction. Among such catalytic metals may be mentioned nickel, copper,metals of the platinum group, etc. These metals may be in a finelydivided form, or maybe spread upon various inert supports. Metals whichare formed by reduction of their oxides, such as reduced nickel, are ofparticular value, because of their high catalytic efliciency. So also,catalytic metals otherwise prepared and possessing high catalyticefliciency can be used to advantage. It is also preferable to carry outthe reaction in iron vessels, rather than glass vessels.

The invention will be further illustrated by the following more detaileddescription of a specific embodiment thereof.

A suitable petroleum fraction, such as is used for lubricating orelectrical purposes, and which has been freed from the gasoline andbenzine fractions. and from the lighter illuminating oils, is agitatedwith the caustic alkali and metal in a suitable receptacle, which may beprovided with a steam jacket or other heating means. and with anagitator or stirrer for causing the agitation of the oil. Thus, to 100liters of oil about 1.7 kilos of finely divided aluminum, e. g, aluminumpowder. and about 5 kilos of caustic soda, are added, and the mixture issuitably agitated and heated to from 70 to 120 C., preferably at from 90to 100 C. The caustic soda is used in considerable excess of that whichis theoretically necessary. The temperature is maintained approximatelyconstant until the desired reaction has been effected and thesludgeforming constituents have been modified and thus eliminated orconverted into non,-

j uents.

sludging constituents. This usually requires several hours, and mayrequire a day or more. 7

The reaction which takes place in the process above described is areduction reaction, the caustic alkali and the aluminum combining withthe evolution of hydrogen, in a nascent condition, within the body ofthe oil. The setting free of this hydrogen in a peculiarly reactiveform, and within the oil body, enables the reduction or saturation ofthe unsaturatedbodies present to take place in an advantageous manner.This action may, in some cases (as with zinc) be promoted by thepresence of a catalytic metal, such as catalytically active nickel.

At the end of the process the metal remaining as such, and the saltsformed, can be removed by settling, or by filtering, or by washing, orotherwise. The oil is thus obtained free from the reagents with which ithas been treated, and freed also by the treatment from itssludge-forming constit- These constituents, of an unsaturated nature,are converted during the treatment into the form of saturated bodies, orinto bodies of higher saturation, by combining with the hydrogen setfree.

Instead of using the caustic alkalis, the alkali carbonates, such assodium carbonate, may be used, although. with less advantage. When usingthe carbonates, water should also be present, for example, water ofcrystalization, so that the desired reaction can take place.

Various forms of powdered metal are available for use in the process.Powdered aluminum is particularly valuable. Granular and leaf aluminumdo notappear to be so good. When iron is used it may be in the form of afine powder, or filings, turnings, and the like, or thin sheet iron outup into small ,pieces. Tinned scrap iron has the advantage of supplyingtwo metals capable of taking part in the reaction; Metal leaf can alsobeused with advantage, especially where the metal leaf is in the form offlakes which readily stay in suspension in the oil.

The action of reduction of'the unsaturated bodies can be supplemented bythe introduction of hydrogen from any suitable external source. Thiswill be of value particularly where a catalytic metal is present topromote the combination of the hydrogen thus added with the unsaturatedconstituents of the oil, the oil bein suitably agitated during thereaction. he present invention accordingly enables the hydrogenation ofoils by means of hydrogen gas and a catalytic metal to be furtherfacilitated and promoted by the simultaneous action of the causticalkali and-of the metal which combines therewith with the liberation ofnascent hydrogen within the oil mass.

Instead of proceeding in the manner above described, a similar reactionmay be carried out by substituting, for the caustic soda or sodiumcarbonate, anhydrous aluminum chloride or similarly acting salts, suchas ferric or zinc or cuprous chloride, etc. These. at propertemperatures, react with aluminum carbide or other carbides mixed withthe oil, when proper sources of combined hydrogen, such as water, arealso present, and hydrogen and hydrocarbons are thus evolved.

The conditions favorable for the interaction of these gases and theunsaturated constituents of the oil are readily established, forexample, a temperature of 120 to 150 C. has been found satisfactory forthis reaction.

As a result of this reaction and treatment, the oil can be freed fromits propensity to sludge and converted into an oil which yields nosludge.

The novel method of the present invention can be applied to otherunsaturated bodies besides those of petroleum fractions, and containingsludge-forming constituents, although the invention is of particularadvantage when applied to such petroleum oils. Such petroleum oilfractions, Which are otherwise unfitted for certain electrical andmechanical uses because of their sludging propensities, can be thus madepractically non-sludging, and can be thus made available for employmentin the industries.

Among. the other unsaturated bodies which can be similarly improved orreduced may be mentioned unsaturated hydrocarbons other than those ofpetroleum fractions, unsaturated animal and vegetable oils and fats suchas the fatty acids and their glycerides, etc. \Vhen treating such fattyacids or their glycerides, the temperatures should in general bemaintained below those which will cause combination of the alkali withthe fatty acid and the formation of soaps, although some formation ofsoaps may take place simultaneously with the reduction or hardening ofthe oils. lVhere soaps are formed during the reaction','they can beremoved at the end of the reaction, and used as soap material, or thefree fatty acids recovered therefrom.

I claim:

1. The process of producing a non-sludging oil from an oil containingsludge-forming constituents, comprising treating the oil with substanceswhich react to evolve hydrogen, the process being carried out at atemperature high enough to cause evolution of hydrogen and ahydrogenation of the sludge-forming constituents of the oil, but nothigh enough to cause a cracking of the oil being treated.

2. The process of producing a non-sludging oil, comprising the step oftreating oil with nascent hydrogen, at a comparatively low temperatureso that no cracking of the oil takes place, whereby the hydrogenconverts the sludge-forming constituents of the oil intonon-sludge-forming constituents.

3. The process of producing a non-sludging oil, comprising treating anappropriate distillate resulting from the distilling of petroleum, withan alkali and a metal, at a temperature that is below the crackintemperature of the oil and that causes t e alkali and metal to react toform hydrogen, the hydrogen combining with the sludgeformingconstituents of the oil to convert them into non-sludge-formingconstituents.

In testimony wherof I afiix my signature.

HERBERT RAYMOND MOODY.

